Compositional Semantics - Computational Linguistics and Talking Robots - page 128

The SRG and the signature in 7.3.5 are each homomorph to the proplet graph
7.3.4. The direction of the homomorphism from SRGs and signatures to pro-
plet graphs is necessitated by the more differentiated structure of proplets as
compared to the corresponding nodes in SRGs or signatures.
A pair of directly connected nodes in a signature constitutes an elementary
signature . In running text, elementary signatures are written as two nodes with
a line in between, e.g., N V. There are the following seven elementary signa-

tures in DBS which are (i) intrapropositional and (ii) transparent: 13

/

7.3.6 T HE SEVEN TRANSPARENT SEMANTIC RELATIONS OF STRUCTURE

subject-verb: 1. N / V

object-verb: 2. N \ V

adjective-noun: 3. A | N

adjective-verb: 4. A | V

conjunct-conjunct: 5. N − N

−

6. V V

A
For example, the signature in 7.3.5 is based on the elementary signatures N

7. A −

/ V

\ |

(subject-verb), N N (adnominal-noun).

It holds in general that the order of the letters in an elementary signature like

V (object-verb), and A

N V does not indicate any primacy of one part of speech over the other. For

now (cf. Sect. 7.6), let us motivate the letter order graphically: in the case of
elementary “

/

” signatures, the first node is shown lower than the
second node in the graph (7.3.4), while in elementary “

/ ,” “ \ ,” and “ |

” signatures the first
node is shown to the left of the second node in the graph (7.4.4).

−

7.4 Producing Natural Language Surfaces from Content

For natural language production from content, the (i) SRG and the (ii) signa-
ture are complemented by two additional structures, called the (iii) numbered
arcs graph or NAG 14 and the (iv) surface realization . Together, these concep-
tual structures provide four simultaneous views (in the conceptual sense) on
a given content. This is illustrated next with the graphical representation of
the content corresponding to the English surface The little girl ate an apple. ,
familiar from 7.2.3, 7.3.2, 7.3.4 and 7.3.5:

13 For the inverse constructions, i.e., (i) extrapropositional and (ii) opaque signatures, see Sect. 7.5.
14 For graph-theoretical and linguistic constraints on NAGs, see Sect. 9.1.